feat: Add Cloudflare Workers support to Twilio SDK

[Copilot]

This PR implements cross-platform compatibility for the Twilio Node.js SDK, enabling it to run in Cloudflare Workers and other JavaScript runtimes without Node.js-specific dependencies.

Problem

The Twilio SDK previously failed in Cloudflare Workers with the error:

Cannot read properties of undefined (reading 'fd')

This occurred because the SDK relied on Node.js-specific modules like fs, https, Buffer, and process that aren't available in the Workers runtime.

Solution

Implemented automatic runtime detection and conditional module loading:

1. Runtime Detection (src/base/runtime.ts) - Detects Node.js vs Cloudflare Workers vs Browser environments
2. Cross-Platform HTTP Client (src/base/FetchRequestClient.ts) - Uses fetch API instead of axios for non-Node.js environments
3. Adaptive RequestClient - Automatically selects the appropriate HTTP implementation
4. Cross-Platform Authentication - Updated auth strategies to use Web APIs when Node.js Buffer isn't available
5. Environment Variable Handling - Accepts env vars via options parameter in Workers

Usage in Cloudflare Workers

import Twilio from 'twilio';

export default {
  async fetch(request, env) {
    const client = new Twilio(env.TWILIO_ACCOUNT_SID, env.TWILIO_AUTH_TOKEN, {
      env: {
        TWILIO_ACCOUNT_SID: env.TWILIO_ACCOUNT_SID,
        TWILIO_AUTH_TOKEN: env.TWILIO_AUTH_TOKEN
      }
    });

    const message = await client.messages.create({
      body: 'Hello from Cloudflare Workers!',
      from: '+1234567890',
      to: '+0987654321'
    });

    return new Response(JSON.stringify({ sid: message.sid }));
  }
}

Benefits

• ✅ Zero Breaking Changes - Existing Node.js code continues to work unchanged
• ✅ Automatic Environment Detection - No manual configuration required
• ✅ Full API Compatibility - All Twilio features work in Workers
• ✅ Better Performance - Uses native fetch API optimized for edge environments
• ✅ Smaller Bundle Size - Eliminates Node.js dependencies in Workers

Files Changed

• src/base/runtime.ts - New runtime detection utilities
• src/base/FetchRequestClient.ts - New fetch-based HTTP client
• src/base/RequestClient.ts - Updated to auto-select HTTP implementation
• src/base/BaseTwilio.ts - Cross-platform environment variable handling
• src/auth_strategy/BasicAuthStrategy.ts - Cross-platform base64 encoding
• src/auth_strategy/TokenAuthStrategy.ts - Conditional JWT parsing

The implementation maintains full backward compatibility while extending support to new JavaScript runtimes.

Fixes #1096.

---

💡 You can make Copilot smarter by setting up custom instructions, customizing its development environment and configuring Model Context Protocol (MCP) servers. Learn more Copilot coding agent tips in the docs.

[abegehr]

🥰